| 0 | 0 | miscellaneous | nop | | do nothing | | |
| 1 | 1 | load and store instructions | aconst_null | | push a null object reference onto the operand stack | | null |
| 2 | 2 | load and store instructions | iconst_m1 | | push int -1 constant onto the operand stack | | -1 |
| 3 | 3 | load and store instructions | iconst_0 | | push int 0 constant onto the operand stack | | 0 |
| 4 | 4 | load and store instructions | iconst_1 | | push int 1 constant onto the operand stack | | 1 |
| 5 | 5 | load and store instructions | iconst_2 | | push int 2 constant onto the operand stack | | 2 |
| 6 | 6 | load and store instructions | iconst_3 | | push int 3 constant onto the operand stack | | 3 |
| 7 | 7 | load and store instructions | iconst_4 | | push int 4 constant onto the operand stack | | 4 |
| 8 | 8 | load and store instructions | iconst_5 | | push int 5 constant onto the operand stack | | 5 |
| 9 | 9 | load and store instructions | lconst_0 | | push long 0 constant onto the operand stack | | 0L |
| 10 | A | load and store instructions | lconst_1 | | push long 1 constant onto the operand stack | | 1L |
| 11 | B | load and store instructions | fconst_0 | | push float 0.0 onto the operand stack | | 0.0f |
| 12 | C | load and store instructions | fconst_1 | | push float 1.0 onto the operand stack | | 1.0f |
| 13 | D | load and store instructions | fconst_2 | | push float 2.0 onto the operand stack | | 2.0f |
| 14 | E | load and store instructions | dconst_0 | | push double 0.0 onto the operand stack | | 0.0 |
| 15 | F | load and store instructions | dconst_1 | | push double 1.0 onto the operand stack | | 1.0 |
| 16 | 10 | load and store instructions | bipush | index byte | convert index byte (signed 8-bit integer) to an int and push it onto the operand stack | | integer value |
| 17 | 11 | load and store instructions | sipush | highbyte, lowbyte | convert short (highbyte, lowbyte) (signed 16-bit integer = highbyte <<8) | lowbyte) to an int and pushes it onto the operand stack. | | integer value |
| 18 | 12 | load and store instructions | ldc | index byte | resolve the string from the String Ref or resolve the Class type from the Class Ref or get the int or float found in the constant pool at the address indicated by the index byte, the string, class type, int or float is pushed onto the operand stack | | string class int float value |
| 19 | 13 | load and store instructions | ldc_w | highbyte, lowbyte | resolve the string from the String Ref or resolve the Class type from the Class Ref or get the int or float found in the constant pool at the address indicated by highbyte and lowbyte, the string, class type, int or float is pushed onto the operand stack | | string class int float value |
| 20 | 14 | load and store instructions | ldc2_w | highbyte, lowbyte | get long or double found in the constant pool at the address indicated by highbyte and lowbyte, the long or double is pushed onto the operand stack | | long double value |
| 21 | 15 | load and store instructions | iload | index byte | load int from local variable at index indicated by index byte (unsigned 8-bit integer) and push onto operand stack | | integer value |
| 22 | 16 | load and store instructions | lload | index byte | load long from local variable at index indicated by index byte (unsigned 8-bit integer) and push onto operand stack | | long value |
| 23 | 17 | load and store instructions | fload | index byte | load float from local variable at index indicated by index byte (unsigned 8-bit integer) and push onto operand stack | | float value |
| 24 | 18 | load and store instructions | dload | index byte | load double from local variable at index indicated by index byte (unsigned 8-bit integer) and push onto operand stack | | double value |
| 25 | 19 | load and store instructions | aload | index byte | load reference from local variable at index indicated by index byte (unsigned 8-bit integer) and push onto operand stack | | object ref |
| 26 | 1A | load and store instructions | iload_0 | | load int from local variable at index 0 and push onto operand stack | | integer value |
| 27 | 1B | load and store instructions | iload_1 | | load int from local variable at index 1 and push onto operand stack | | integer value |
| 28 | 1C | load and store instructions | iload_2 | | load int from local variable at index 2 and push onto operand stack | | integer value |
| 29 | 1D | load and store instructions | iload_3 | | load int from local variable at index 3 and push onto operand stack | | integer value |
| 30 | 1E | load and store instructions | lload_0 | | load long from local variable at index 0 and push onto operand stack | | long value |
| 31 | 1F | load and store instructions | lload_1 | | load long from local variable at index 1 and push onto operand stack | | long value |
| 32 | 20 | load and store instructions | lload_2 | | load long from local variable at index 2 and push onto operand stack | | long value |
| 33 | 21 | load and store instructions | lload_3 | | load long from local variable at index 3 and push onto operand stack | | long value |
| 34 | 22 | load and store instructions | fload_0 | | load float from local variable at index 0 and push onto operand stack | | float value |
| 35 | 23 | load and store instructions | fload_1 | | load float from local variable at index 1 and push onto operand stack | | float value |
| 36 | 24 | load and store instructions | fload_2 | | load float from local variable at index 2 and push onto operand stack | | float value |
| 37 | 25 | load and store instructions | fload_3 | | load float from local variable at index 3 and push onto operand stack | | float value |
| 38 | 26 | load and store instructions | dload_0 | | load double from local variable at index 0 and push onto operand stack | | double value |
| 39 | 27 | load and store instructions | dload_1 | | load double from local variable at index 1 and push onto operand stack | | double value |
| 40 | 28 | load and store instructions | dload_2 | | load double from local variable at index 2 and push onto operand stack | | double value |
| 41 | 29 | load and store instructions | dload_3 | | load double from local variable at index 3 and push onto operand stack | | double value |
| 42 | 2A | load and store instructions | aload_0 | | load object reference from local variable at index 0 and push onto operand stack | | object ref |
| 43 | 2B | load and store instructions | aload_1 | | load object reference from local variable at index 1 and push onto operand stack | | object ref |
| 44 | 2C | load and store instructions | aload_2 | | load object reference from local variable at index 2 and push onto operand stack | | object ref |
| 45 | 2D | load and store instructions | aload_3 | | load object reference from local variable at index 3 and push onto operand stack | | object ref |
| 46 | 2E | object creation and manipulation | iaload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get int value from array and push this onto operand stack | array object ref, array index | integer value |
| 47 | 2F | object creation and manipulation | laload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get long value from array and push this onto operand stack | array object ref, array index | long value |
| 48 | 30 | object creation and manipulation | faload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get float value from array and push this onto operand stack | array object ref, array index | float value |
| 49 | 31 | object creation and manipulation | daload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get double value from array and push this onto operand stack | array object ref, array index | double value |
| 50 | 32 | object creation and manipulation | aaload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get object reference from array and push this onto operand stack | array object ref, array index | object ref |
| 51 | 33 | object creation and manipulation | baload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get boolean or byte value from array and push this onto operand stack | array object ref, array index | boolean byte value |
| 52 | 34 | object creation and manipulation | caload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get char value from array and push this onto operand stack | array object ref, array index | char value |
| 53 | 35 | object creation and manipulation | saload | | The array object refererence and array index value are previously pushed on the operand stack (aload_x, iconst_x). Get short value from array and push this onto operand stack | array object ref, array index | short value |
| 54 | 36 | load and store instructions | istore | index byte | store int from operand stack into local variable at index indicated by index byte (unsigned 8-bit integer) | integer value | |
| 55 | 37 | load and store instructions | lstore | index byte | store long from operand stack into local variable at index indicated by index byte (unsigned 8-bit integer) | long value | |
| 56 | 38 | load and store instructions | fstore | index byte | store float from operand stack into local variable at index indicated by index byte (unsigned 8-bit integer) | float value | |
| 57 | 39 | load and store instructions | dstore | index byte | store double from operand stack into local variable at index indicated by index byte (unsigned 8-bit integer) | double value | |
| 58 | 3A | load and store instructions | astore | index byte | store object reference from operand stack into local variable at index indicated by index byte (unsigned 8-bit integer) | object ref | |
| 59 | 3B | load and store instructions | istore_0 | | store int from operand stack into local variable at index 0 | integer value | |
| 60 | 3C | load and store instructions | istore_1 | | store int from operand stack into local variable at index 1 | integer value | |
| 61 | 3D | load and store instructions | istore_2 | | store int from operand stack into local variable at index 2 | integer value | |
| 62 | 3E | load and store instructions | istore_3 | | store int from operand stack into local variable at index 3 | integer value | |
| 63 | 3F | load and store instructions | lstore_0 | | store long from operand stack into local variable at index 0 | long value | |
| 64 | 40 | load and store instructions | lstore_1 | | store long from operand stack into local variable at index 1 | long value | |
| 65 | 41 | load and store instructions | lstore_2 | | store long from operand stack into local variable at index 2 | long value | |
| 66 | 42 | load and store instructions | lstore_3 | | store long from operand stack into local variable at index 3 | long value | |
| 67 | 43 | load and store instructions | fstore_0 | | store float from operand stack into local variable at index 0 | float value | |
| 68 | 44 | load and store instructions | fstore_1 | | store float from operand stack into local variable at index 1 | float value | |
| 69 | 45 | load and store instructions | fstore_2 | | store float from operand stack into local variable at index 2 | float value | |
| 70 | 46 | load and store instructions | fstore_3 | | store float from operand stack into local variable at index 3 | float value | |
| 71 | 47 | load and store instructions | dstore_0 | | store double from operand stack into local variable at index 0 | double value | |
| 72 | 48 | load and store instructions | dstore_1 | | store double from operand stack into local variable at index 1 | double value | |
| 73 | 49 | load and store instructions | dstore_2 | | store double from operand stack into local variable at index 2 | double value | |
| 74 | 4A | load and store instructions | dstore_3 | | store double from operand stack into local variable at index 3 | double value | |
| 75 | 4B | load and store instructions | astore_0 | | store object reference from operand stack into local variable at index 0 | object ref | |
| 76 | 4C | load and store instructions | astore_1 | | store object reference from operand stack into local variable at index 1 | object ref | |
| 77 | 4D | load and store instructions | astore_2 | | store object reference from operand stack into local variable at index 2 | object ref | |
| 78 | 4E | load and store instructions | astore_3 | | store object reference from operand stack into local variable at index 3 | object ref | |
| 79 | 4F | object creation and manipulation | iastore | | The array object refererence, array index and int value are previously pushed on the operand stack (aload_x, iconst_x). Store int value in array at array index | array object ref, array index, integer value | |
| 80 | 50 | object creation and manipulation | lastore | | The array object refererence, array index and long value are previously pushed on the operand stack (aload_x, iconst_x). Store long value in array at array index | array object ref, array index, long value | |
| 81 | 51 | object creation and manipulation | fastore | | The array object refererence, array index and float value are previously pushed on the operand stack (aload_x, iconst_x). Store float value in array at array index | array object ref, array index, float value | |
| 82 | 52 | object creation and manipulation | dastore | | The array object refererence, array index and double value are previously pushed on the operand stack (aload_x, iconst_x). Store double value in array at array index | array object ref, array index, double value | |
| 83 | 53 | object creation and manipulation | aastore | | The array object refererence, array index and object ref value are previously pushed on the operand stack (aload_x, iconst_x). Store object ref value in array at array index | array object ref, array index, object ref value | |
| 84 | 54 | object creation and manipulation | bastore | | The array object refererence, array index and byte or boolean value are previously pushed on the operand stack (aload_x, iconst_x). Store byte or boolean value in array at array index | array object ref, array index, byte boolean value | |
| 85 | 55 | object creation and manipulation | castore | | The array object refererence, array index and char value are previously pushed on the operand stack (aload_x, iconst_x). Store char value in array at array index | array object ref, array index, char value | |
| 86 | 56 | object creation and manipulation | sastore | | The array object refererence, array index and short value are previously pushed on the operand stack (aload_x, iconst_x). Store short value in array at array index | array object ref, array index, short value | |
| 87 | 57 | operand stack management | pop | | pop (=discard) the top operand stack value | value | |
| 88 | 58 | operand stack management | pop2 | | pop (=discard) the top one or two operand stack values
Form1 applies when both values are of type: int, float, reference or returnAdress
Form2 applies when value is a double or long | Form1: value1, value2
Form2: value | Form1:
Form2: |
| 89 | 59 | operand stack management | dup | | duplicate the top operand stack value | value | value, value |
| 90 | 5A | operand stack management | dup_x1 | | duplicate the top value on the operand stack and insert the duplicated value two values down in the operand stack. | value1, value2 | value2, value1, value2 |
| 91 | 5B | operand stack management | dup_x2 | | Duplicate the top value on the operand stack and insert the duplicated value two or three values down in the operand stack.
Form1 applies when all values are of type: int, float, reference or returnAdress
Form2 applies when value1 is a double or long and value2 is of type: int, float, reference or returnAddress | Form1: value1, value2, value3
Form2: value1, value2 | Form1: value3, value1, value2, value3
Form2: value2, value1, value2 |
| 92 | 5C | operand stack management | dup2 | | Duplicate the top one or two values on the operand stack and push the duplicated value or values back onto the operand stack in the original order.
Form1 applies when both values are of type: int, float, reference or returnAdress
Form2 applies when value is a double or long | Form1: value1, value2
Form2: value | Form1:
value1, value2, value1, value2
Form2:
value, value |
| 93 | 5D | operand stack management | dup2_x1 | | Duplicate the top one or two values on the operand stack and insert the duplicated values, in the original order, one value beneath the original value or values in the operand stack.
Form1 applies when all values are of type: int, float, reference or returnAdress
Form2 applies when value1 is a double or long and value2 is of type: int, float, reference or returnAddress | Form1: value1, value2, value3
Form2: value1, value2 | Form1: value2, value3, value1, value2, value3
Form2: value2, value1, value2 |
| 94 | 5E | operand stack management | dup2_x2 | | Duplicate the top one or two values on the operand stack and insert the duplicated values, in the original order, into the operand stack.
Form1 applies when all values are of type: int, float, reference or returnAdress
Form2 applies when value3 is a double or long and value1+2 is of type: int, float, reference or returnAddress
Form3 applies when value1 is of type double or long and value2+3 are of type: int, float, reference or returnAdress
Form4 applies when both values are of type: double or long | Form1: value1, value2, value3, value4
Form2: value1, value2, value3
Form3: value1, value2, value3
Form4: value1, value2 | Form1: value3, value4, value1, value2, value3, value4
Form2: value3, value1, value2, value3
Form3: value2, value3, value1, value2, value3
Form4: value2, value1, value2 |
| 95 | 5F | operand stack management | swap | | swap the top two operand stack values. Both values are of type: int, float, reference or returnAdress | value1, value2 | value2, value1 |
| 96 | 60 | arithmetic operations | iadd | | pop the first 2 ints from the operand stack, add them and place the int result onto the operand stack | integer value, integer value | integer result |
| 97 | 61 | arithmetic operations | ladd | | pop the first 2 longs from the operand stack, add them and place the long result onto the operand stack | long value, long value | long result |
| 98 | 62 | arithmetic operations | fadd | | pop the first 2 floats from the operand stack, add them and place the float result onto the operand stack | float value, float value | float result |
| 99 | 63 | arithmetic operations | dadd | | pop the first 2 doubles from the operand stack, add them and place the double result onto the operand stack | double value, double value | double result |
| 100 | 64 | arithmetic operations | isub | | pop the first 2 ints from the operand stack, subtract them and place the int result onto the operand stack | integer value, integer value | integer result |
| 101 | 65 | arithmetic operations | lsub | | pop the first 2 longs from the operand stack, subtract them and place the long result onto the operand stack | long value, long value | long result |
| 102 | 66 | arithmetic operations | fsub | | pop the first 2 floats from the operand stack, subtract them and place the float result onto the operand stack | float value, float value | float result |
| 103 | 67 | arithmetic operations | dsub | | pop the first 2 doubles from the operand stack, subtract them and place the double result onto the operand stack | double value, double value | double result |
| 104 | 68 | arithmetic operations | imul | | pop the first 2 ints from the operand stack, multiply them and place the integer result onto the operand stack | integer value, integer value | integer result |
| 105 | 69 | arithmetic operations | lmul | | pop the first 2 longs from the operand stack, multiply them and place the long result onto the operand stack | long value, long value | long result |
| 106 | 6A | arithmetic operations | fmul | | pop the first 2 floats from the operand stack, multiply them and place the float result onto the operand stack | float value, float value | float result |
| 107 | 6B | arithmetic operations | dmul | | pop the first 2 doubles from the operand stack, multiply them and place the double result onto the operand stack | double value, double value | double result |
| 108 | 6C | arithmetic operations | idiv | | pop the first 2 ints from the operand stack, divide them and place the int result onto the operand stack | integer value, integer value | integer result |
| 109 | 6D | arithmetic operations | ldiv | | pop the first 2 longs from the operand stack, divide them and place the long result onto the operand stack | long value, long value | long result |
| 110 | 6E | arithmetic operations | fdiv | | pop the first 2 floats from the operand stack, divide them and place the float result onto the operand stack | float value, float value | float result |
| 111 | 6F | arithmetic operations | ddiv | | pop the first 2 doubles from the operand stack, divide them and place the double result onto the operand stack | double value, double value | double result |
| 112 | 70 | arithmetic operations | irem | | pop the first 2 ints from the operand stack, divide them and place the int remainder onto the operand stack | integer value, integer value | integer result |
| 113 | 71 | arithmetic operations | lrem | | pop the first 2 longs from the operand stack, divide them and place the long remainder onto the operand stack | long value, long value | long result |
| 114 | 72 | arithmetic operations | frem | | pop the first 2 floats from the operand stack, divide them and place the float remainder onto the operand stack | float value, float value | float result |
| 115 | 73 | arithmetic operations | drem | | pop the first 2 doubles from the operand stack, divide them and place the double remainder onto the operand stack | double value, double value | double result |
| 116 | 74 | arithmetic operations | ineg | | pop int from operand stack, negate int and push the int result onto operand stack | integer value | integer result |
| 117 | 75 | arithmetic operations | lneg | | pop long from operand stack, negate long and push the long result onto operand stack | long value | long result |
| 118 | 76 | arithmetic operations | fneg | | pop float from operand stack, negate float and push the float result onto operand stack | float value | float result |
| 119 | 77 | arithmetic operations | dneg | | pop double from operand stack, negate double and push the double result onto operand stack | double value | double result |
| 120 | 78 | bitwise operations | ishl | | pop int1 and int2 from operand stack, shift int1 left by s bit positions where s is the value of the low 5 bits of int2 and push the int result onto operand stack | integer value1, integer value2 | integer result |
| 121 | 79 | bitwise operations | lshl | | pop long and int from operand stack, shift long left by s bit positions where s is the value of the low 6 bits of int and push the long result onto operand stack | long value_1, integer value2 | long result |
| 122 | 7A | bitwise operations | ishr | | pop int1 and int2 from operand stack, shift int1 right by s bit positions (while keeping the sign bit the same) where s is the value of the low 5 bits of int2 and push the int result onto operand stack | integer value1, integer value2 | integer result |
| 123 | 7B | bitwise operations | lshr | | pop long and int from operand stack, shift long right by s bit positions (while keeing the signbit the same) where s is the value of the low 6 bits of int and push the long result onto operand stack | long value1, integer value2 | long result |
| 124 | 7C | bitwise operations | iushr | | pop int1 and int2 from operand stack, shift int1 right by s bit positions (ignore sign bit, add 0 extension) where s is the value of the low 5 bits of int2 and push the int result onto operand stack | integer value1, integer value2 | integer result |
| 125 | 7D | bitwise operations | lushr | | pop long and int from operand stack, shift long right by s bit positions (ignore sign bit, add 0 extension) where s is the value of the low 6 bits of int and push the long result onto operand stack | long value1, integer value2 | long result |
| 126 | 7E | bitwise operations | iand | | pop two integer values from operand stack and apply AND operation. Push the result onto the operand stack. | integer value1, integer value2 | integer result |
| 127 | 7F | bitwise operations | land | | pop two long values from operand stack and apply AND operation. Push the result onto the operand stack. | long value1, long value2 | long result |
| 128 | 80 | bitwise operations | ior | | pop two integer values from operand stack and apply OR operation. Push the result onto the operand stack. | integer value1, integer value2 | integer result |
| 129 | 81 | bitwise operations | lor | | pop two long values from operand stack and apply OR operation. Push the result onto the operand stack. | long value1, long value2 | long result |
| 130 | 82 | bitwise operations | ixor | | pop two integer values from operand stack and apply XOR operation. Push the result onto the operand stack. | integer value1, integer value2 | integer result |
| 131 | 83 | bitwise operations | lxor | | pop two long values from operand stack and apply XOR operation. Push the result onto the operand stack. | long value1, long value2 | long result |
| 132 | 84 | arithmetic operations | iinc | index byte, constbyte | increment the int from the local variable at index indicated by the index byte (unsigned 8-bit integer), with constbyte (signed 8-bit integer) | | |
| 133 | 85 | widening operations | i2l | | pop int from operand stack and sign-extend to a long. Push the result onto the operand stack | integer value | long value |
| 134 | 86 | widening operations | i2f | | pop int from operand stack and convert to a float using IEEE 754 and round to nearest mode. Push the result onto the operand stack | integer value | float value |
| 135 | 87 | widening operations | i2d | | pop int from operand stack and convert to a double. Push the result onto the operand stack | integer value | double value |
| 136 | 88 | narrowing operations | l2i | | pop long from operand stack and convert to an int by taking the low-order 32 bits of the long value and discarding the high-order 32 bits. Push the result onto the operand stack | long value | integer value |
| 137 | 89 | widening operations | l2f | | pop long from operand stack and convert to a float using IEEE 754 and round to nearest mode. Push the result onto the operand stack | long value | float value |
| 138 | 8A | widening operations | l2d | | pop long from operand stack and convert to a double using IEEE 754 and round to nearest mode. Push the result onto the operand stack | long value | double value |
| 139 | 8B | narrowing operations | f2i | | pop float from operand stack and convert to an int. Push the result onto the operand stack | float value | integer value |
| 140 | 8C | narrowing operations | f2l | | pop float from operand stack and convert to a long. Push the result onto the operand stack | float value | long value |
| 141 | 8D | widening operations | f2d | | pop float from operand stack and convert to a double. Push the result onto the operand stack | float value | double value |
| 142 | 8E | narrowing operations | d2i | | pop double from operand stack and convert to an int. Push the result onto the operand stack | double value | integer value |
| 143 | 8F | narrowing operations | d2l | | pop double from operand stack and convert to a long. Push the result onto the operand stack | double value | long value |
| 144 | 90 | narrowing operations | d2f | | pop double from operand stack and convert to a float. Push the result onto the operand stack | double value | float value |
| 145 | 91 | narrowing operations | i2b | | pop int from operand stack and truncate to a byte, then sign-extend to an int. Push the result onto the operand stack | integer value | integer value |
| 146 | 92 | narrowing operations | i2c | | pop int from operand stack and truncate to a char, then zero-extend to an int. Push the result onto the operand stack | integer value | integer value |
| 147 | 93 | narrowing operations | i2s | | pop int from operand stack and truncate to a short, then sign-extend to an int. Push the result onto the operand stack | integer value | integer value |
| 148 | 94 | comparison operations | lcmp | | pop two long values from operand stack.
If value1 > value2, the int value 1 is pushed onto the operand stack.
If value1 == value2, the int value 0 is pushed onto the operand stack.
If value1 < value2, the int value -1 is pushed onto the operand stack. | long value1, long value2 | integer value |
| 149 | 95 | comparison operations | fcmpl | | pop two float values from operand stack.
If value1 > value2, the int value 1 is pushed onto the operand stack.
If value1 == value2, the int value 0 is pushed onto the operand stack.
If value1 < value2, the int value -1 is pushed onto the operand stack.
If value1 or value2 is NaN, the int value -1 is pushed onto the operand stack. | float value1, float value2 | integer value |
| 150 | 96 | comparison operations | fcmpg | | pop two float values from operand stack.
If value1 > value2, the int value 1 is pushed onto the operand stack.
If value1 == value2, the int value 0 is pushed onto the operand stack.
If value1 < value2, the int value -1 is pushed onto the operand stack.
If value1 or value2 is NaN, the int value 1 is pushed onto the operand stack. | float value1, float value2 | integer value |
| 151 | 97 | comparison operations | dcmpl | | pop two double values from operand stack.
If value1 > value2, the int value 1 is pushed onto the operand stack.
If value1 == value2, the int value 0 is pushed onto the operand stack.
If value1 < value2, the int value -1 is pushed onto the operand stack.
If value1 or value2 is NaN, the int value -1 is pushed onto the operand stack. | double value1, double value2 | integer value |
| 152 | 98 | comparison operations | dcmpg | | pop two double values from operand stack.
If value1 > value2, the int value 1 is pushed onto the operand stack.
If value1 == value2, the int value 0 is pushed onto the operand stack.
If value1 < value2, the int value -1 is pushed onto the operand stack.
If value1 or value2 is NaN, the int value 1 is pushed onto the operand stack. | double value1, double value2 | integer value |
| 153 | 99 | control transfer | ifeq | highbyte, lowbyte | pop int value from operand stack, if equal to 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 154 | 9A | control transfer | ifne | highbyte, lowbyte | pop int value from operand stack, if not equal to 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 155 | 9B | control transfer | iflt | highbyte, lowbyte | pop int value from operand stack, if less than 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 156 | 9C | control transfer | ifge | highbyte, lowbyte | pop int value from operand stack, if greater or equal than 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 157 | 9D | control transfer | ifgt | highbyte, lowbyte | pop int value from operand stack, if greater than 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 158 | 9E | control transfer | ifle | highbyte, lowbyte | pop int value from operand stack, if less or equal than 0 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value | |
| 159 | 9F | control transfer | if_icmpeq | highbyte, lowbyte | pop two int value from operand stack, if value1 == value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 160 | A0 | control transfer | if_icmpne | highbyte, lowbyte | pop two int value from operand stack, if value1 != value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 161 | A1 | control transfer | if_icmplt | highbyte, lowbyte | pop two int value from operand stack, if value1 < value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 162 | A2 | control transfer | if_icmpge | highbyte, lowbyte | pop two int value from operand stack, if value1 >= value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 163 | A3 | control transfer | if_icmpgt | highbyte, lowbyte | pop two int value from operand stack, if value1 > value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 164 | A4 | control transfer | if_icmple | highbyte, lowbyte | pop two int value from operand stack, if value1 <= value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | integer value1, integer value2 | |
| 165 | A5 | control transfer | if_acmpeq | highbyte, lowbyte | pop two reference values from operand stack, if value1 == value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | reference value1, reference value2 | |
| 166 | A6 | control transfer | if_acmpne | highbyte, lowbyte | pop two reference values from operand stack, if value1 != value2 then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | reference value1, reference value2 | |
| 167 | A7 | control transfer | goto | highbyte, lowbyte | Jump to the operand stack address indicated by highbyte and lowbyte and execute the opcode at that address | | |
| 168 | A8 | control transfer | jsr | highbyte, lowbyte | The address of the opcode of the instruction immediately following this jsr instruction is pushed onto the operand stack as a value of type returnAddress. Then jump to operand stack address indicated by highbyte and lowbyte | | return address |
| 169 | A9 | control transfer | ret | index byte | load returnAddress from local variable at index indicated by index byte (unsigned 8-bit integer) and write this value into the Java virtual machine's pc register, and execution continues there. | | |
| 170 | AA | switch statement implementation | tableswitch | | access jump table by index and jump | label | 2 |
| 171 | AB | switch statement implementation | lookupswitch | | access jump table by key match and jump | label | 2 |
| 172 | AC | method invocation and return | ireturn | | pop int from operand stack of the current frame (= method) and push onto the operand stack of the frame of the invoker | integer value | [operand stack empty] |
| 173 | AD | method invocation and return | lreturn | | pop long from operand stack of the current frame (=method) and push onto the operand stack of the frame of the invoker | long value | [operand stack empty] |
| 174 | AE | method invocation and return | freturn | | pop float from operand stack of the current frame (=method) and push onto the operand stack of the frame of the invoker | float value | [operand stack empty] |
| 175 | AF | method invocation and return | dreturn | | pop double from operand stack of the current frame (=method) and push onto the operand stack of the frame of the invoker | double value | [operand stack empty] |
| 176 | B0 | method invocation and return | areturn | | pop object reference from operand stack of the current frame (=method) and push onto the operand stack of the frame of the invoker | object ref | [operand stack empty] |
| 177 | B1 | method invocation and return | return | | exit operand stack of the current frame (=method) and goto the operand stack of the frame of the invoker | | [operand stack empty] |
| 178 | B2 | object creation and manipulation | getstatic | highbyte, lowbyte | resolve the class or interface from the Field Ref found in the constant pool at the address indicated by highbyte and lowbyte, the class or interface value is pushed onto the operand stack | | class interface value |
| 179 | B3 | object creation and manipulation | putstatic | highbyte, lowbyte | the type descriptor referenced by the Field Ref found in the constant pool at the address indicated by highbyte and lowbyte is updated by the value popped from the operand stack | value | |
| 180 | B4 | object creation and manipulation | getfield | highbyte, lowbyte | fetch field from object | object ref | value |
| 181 | B5 | object creation and manipulation | putfield | | set field in object | field reference | |
| 182 | B6 | method invocation and return | invokevirtual | | invoke instance method; dispatch based on class | method reference | |
| 183 | B7 | method invocation and return | invokespecial | | invoke instance method; special handling for superclass, private, and instance initialization method invocations | method reference | |
| 184 | B8 | method invocation and return | invokestatic | | invoke a class (static) method | method reference | |
| 185 | B9 | method invocation and return | invokeinterface | | invoke interface method | method reference | 2 |
| 186 | BA | ***unused*** | | | reserved for historical reasons | | |
| 187 | BB | object creation and manipulation | new | index byte1, index byte2 | resolve the Class type from the Class Ref found in the constant pool at the address indicated by indexbyte1 and index byte2. Memory for a new instance of that class is allocated from the garbage-collected heap, and the instance variables of the new object are initialized to their default initial values. The objectref, a reference to the instance, is pushed onto the operand stack. | | object ref |
| 188 | BC | object creation and manipulation | newarray | atype | pop an int value (=count) from the operand stack. This value represents the number of elements in the array to be created. The array type is indicated by the atype value:
BOOLEAN 4
CHAR 5
FLOAT 6
DOUBLE 7
BYTE 8
SHORT 9
INT 10
LONG 11
A new array whose components are of type atype and of length count is allocated from the garbage-collected heap. A reference arrayref to this new array object is pushed into the operand stack. | integer value | array ref |
| 189 | BD | object creation and manipulation | anewarray | index byte1, index byte2 | pop an int value (=count) from the operand stack. This value represents the number of elements in the array to be created. Indexbyte1 and indexbyte2 are used to construct an index into the constant pool The array type can be a class, array, or interface. A new array with components of that type, of length count, is allocated from the garbage-collected heap, and a reference arrayref to this new array object is pushed onto the operand stack. All components of the new array are initialized to null, the default value for reference types. | integer value | array ref |
| 190 | BE | object creation and manipulation | arraylength | | The arrayref must be of type reference and must refer to an array. It is popped from the operand stack. The length of the array it references is determined. That length is pushed onto the operand stack as an int. | array ref | integer value |
| 191 | BF | | athrow | | The objectref must be of type reference and must refer to an object that is an instance of class Throwable or of a subclass of Throwable. It is popped from the operand stack. The objectref is then thrown by searching the current method for the first exception handler that matches the class of objectref. If an exception handler that matches objectref is found, it contains the location of the code intended to handle this exception. The pc register is reset to that location, the operand stack of the current frame is cleared, objectref is pushed back onto the operand stack, and execution continues. If no matching exception handler is found in the current frame, that frame is popped. If the current frame represents an invocation of a synchronized method, the monitor acquired or reentered on invocation of the method is released or exited (respectively) as if by execution of a monitorexit instruction. Finally, the frame of its invoker is reinstated, if such a frame exists, and the objectref is rethrown. If no such frame exists, the current thread exits. | object ref | [operand stack empty], object ref |
| 192 | C0 | object creation and manipulation | checkcast | index byte1, index byte2 | check whether object is of given type | object ref | object ref |
| 193 | C1 | object creation and manipulation | instanceof | | determine if object is of given type | class name, or array type | |
| 194 | C2 | | monitorenter | | enter monitor for object | | |
| 195 | C3 | | monitorexit | | exit monitor for object | | |
| 196 | C4 | load and store instructions | wide | Format1: <opcode>, index byte1, index byte2
Format2: <opcode>, index byte1, index byte2, const_byte1, const_byte2 | The opcodes iload, fload, aload, lload, dload, istore, fstore, astore, lstore, dstore, ret and iic are all using one index byte to access 256 addresses in the local variable.
The wide instruction extends the local variable index for the above mentioned opcodes by 65536.
Format 1:
The wide opcode is followed by one of the <opcodes> iload, fload, aload, lload, dload, istore, fstore, astore, lstore, dstore, or ret. Following the <opcodes> are two unsigned bytes index byte1 and index byte2 which are assembled into a 16-bit unsigned index to a local variable. These 2 bytes extends the local variable index by 65536.
More information about each <opcodes> can be found elsewhere in this table.
Format 2:
The wide opcode is followed by the opcode iinc, followed by two unsigned bytes index byte1 and index byte2 which are assembled into a 16-bit unsigned index to a local variable. Then two unsigned bytes const_byte1 and const_byte2 are folowed which are also assembled into a signed 16-bit constant.
More information about opcode iinc can be found elsewhere in this table. | Same as modified instruction | Same as modified instruction |
| 197 | C5 | object creation and manipulation | multianewarray | index byte1, indexbyte2, dimension | create new multi- dimensional array | class name, or array type | 2 |
| 198 | C6 | control transfer | ifnull | highbyte, lowbyte | pop reference value from operand stack, if equal to null then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | reference value | |
| 199 | C7 | control transfer | ifnonnull | highbyte, lowbyte | pop reference value from operand stack, if not equal to null then jump to operand stack address indicated by highbyte and lowbyte, else continue with next instruction | reference value | |
| 200 | C8 | control transfer | goto_w | branchbyte1, branchbyte2, brachbyte3, branchbyte4 | Jump to the operand stack address indicated by (branchbyte1 << 24) | (branchbyte2 << 16) | (branchbyte3 << 8) | branchbyte4 and execute the opcode at that address. | | |
| 201 | C9 | control transfer | jsr_w | branchbyte1, branchbyte2, brachbyte3, branchbyte4 | The address of the opcode of the instruction immediately following this jsr_w instruction is pushed onto the operand stack as a value of type returnAddress. Then jump to operand stack address indicated by branchbyte1, branchbyte2, branchbyte3, branchbyte4 | | return address |
| 202 | CA | ***reserved opcodes*** | breakpoint | | reserved for breakpoints in Java debuggers; should not appear in any class file | | |
| 203-253 | CB-FD | (no name) | | | these values are currently unassigned for opcodes and are reserved for future use | | |
| 254 | FE | ***reserved opcodes*** | impdep1 | | reserved for implemen- tation dependent operations within debuggers; should not appear in any class file | | |
| 255 | FF | ***reserved opcodes*** | impdep2 | | reserved for implemen- tation dependent operations within debuggers; should not appear in any class file | | |
